Telecommunications is currently undergoing a revolution brought about by the explosive growth of Internet traffic. Behind this growth are the millions of new users, demand for richer content like multimedia and the migration of voice and data traffic onto the Internet and associated backbone networks. Increasingly, voice traffic will be carried on new Internet Protocol (IP) networks and Asynchronous Transfer Mode (ATM) networks.
In fact, the public switched telephone network (“PSTN”) is evolving rapidly from a closed system to an open network architecture that will enable telecommunication carriers to differentiate themselves with new service offerings provided by open software platforms. Users are demanding more service flexibility along with reliability equivalent to current PSTNs. Also, telecommunication carriers are reluctant to discard billions of dollars of legacy equipment. However, the telecommunication carriers realize that the PSTNs will need to evolve to handle the demands of today's users.
To take advantage of digital network capabilities, telecommunication carriers are employing carrier class voice gateway products to transform PSTNs into a more flexible, scalable solution that can accommodate the increasing data traffic. Carrier class voice gateway products are typically positioned between a Class 5 central office switch and the packet or cell-based digital network that carries the traffic. Two main functions of the carrier class voice gateways are to set up the call based on the signaling protocol used and to convert the time division multiplexed (TDM) voice samples into data packets or cells.
Currently, the dominant formats for carrying voice on digital networks employing carrier class voice gateways include Voice of IP (VoIP), Voice over ATM (VoATM) using ATM Adaptation Layer 2 (AAL2) and VoATM using AAL1. Currently available systems can apply the required headers needed for VoIP processing and perform the segmentation and reassembly (SAR) functions needed for VoATM using AAL1. However, implementing SAR functions for VoATM using AAL2 has additional complexities and increased processing requirements due to the protocol and format of AAL2. The ATM networks themselves also impose additional timing constraints due to the speed requirements associated with cell transmission. Current carrier class voice gateways have not been able to overcome the complexities of AAL2 and the timing requirements to implement segmentation and reassembly functions for AAL2.
Accordingly, what is needed in the art is a system to overcome the deficiencies of the prior art.